The US 2013/0182925 A1 discloses a method of initially registering a first set of image data and a second set of image data. A further registration of the images is then performed in a region that is automatically or manually selected. The initial registration may for example be a free-form transformation, while the further registration is a rigid registration. In a final step, the initial and the further registrations may be merged.
The US 2005/065421 A1 discloses a method in which first anatomical and functional images are co-registered, and second anatomical and functional images, acquired at a later stage, are co-registered. A global, rigid registration is performed on the first and second anatomical images. Moreover, a volume of interest (ROI) is identified in the first co-registered composite image data set and a local, non-rigid registration is performed on this ROI and a corresponding ROI within the globally registered image data set.
The WO 2007/066294 A2 discloses a procedure in which several registrations of a first image and a second image are displayed on a display during a medical intervention. A physician can then visually select one of the registrations for subsequent use.
The WO 20121025855 A1 discloses the registration of anatomical images and emission images. In one embodiment, a global rigid registration is followed by a local non-rigid registration of a region of interest.